Java JPanel在BorderLayout中的定位

Question

Can I expand a child panel all the way from BorderLayout.LINE_START to BorderLayout.LINE_END , fill all the space from right to left including the center ?

I am trying to accomplish as below...

+-------------------------+
|                         |
+-------------------------+
|     PANEL OCCUPYING     |
|         ALL THIS        |
|          SPACE          |
+-------------------------+
|                         |
+-------------------------+

Answer 1

That looks like the CENTER of the BorderLayout.

Read the section from the Swing tutorial on How to Use BorderLayout for more information and examples.

for some reason, I keep getting empty spaces on the right and left...

The CENTER will occupy all the space available. So it depends on the component that you add to the CENTER . Maybe you are adding a panel and the panel expands, but the component on the panel doesn't expand because by default a panel uses a FlowLayout and FlowLayout respects the preferred size of the components added to it.